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Monday, October 22, 2012

Ideas for the solar shader

19 Oct 2012: The large window will have a solar shader, and initially, I can re-fix up the mirror-shader that was made for the previous window. That worked fine for the winter. For Summer use, we need a more cantilevered shader, and I planned a triple louvre shader cantilevering about 700-800mm. I have a present method of making louvres that keeps the aluminium flat, and has a stiffening rib behind. The outward facing surface can be mirrored with Mylar. I want the outermost louvre to tilt fully so it directs sunlight into the window, but the two nearer the wall to tilt only slightly.

After doing some sketches, I devised the principles of tilting the first two and having a reciprocating tilt for the third. As it is not clear what the dimensions would be for this to work smoothly, the only way to progress the design was to make a working model. Even without dimensions, the mechanism would reveal itself.

This model, in cardboard, is about 50% scale and the third louvre needs a cranked or angled tilting lever. this is a good way to establish if the principle works. It does.

This is in the Winter setting. With the cranked lever above the right hand louvre, it is possible to get all the louvres parallel in the winter and the summer setting. The outer faces of the louvres face out correctly. The right hand louvre has a mirror finish and reflects sunlight onto the window. The left and middle face the sky and reflect daylight onto the window.

The problem with the reciprocating louvre is that there is no useful middle setting. If I make them to beall parallel, there would be some in-between positions.

The Summer setting is shown here, and it is really 'neat' the way the third louvre flips as one moves the control lever.
If the louvres remain one-sided like my existing one on the previous window, then this would be the best solution, especially if the outer one is a bit larger.

This shows the location of the shader on the south wall above the large window. I might use the old existing shader at the sill level to bounce light up into the south window.

As I was going home after making this, my colleague suggesting making a wing (mandala) shape for the louvre, so that they could be double sided, with both sides reflecting. I realised that with my experience of doing the metal roofing, I know enough now to make a wing shape - with the 0.7mm alloy. The 1.2mm is too stiff to do it, but I tested the 0.7mm and it is quite possible.
I have also managed to find some mirror finish aluminium (but only 0.5mm gauge) and I am weather testing a piece of it in the front garden now.

March 2015: Work on the solar dehydrator has been progressing well, and it is nearly complete, lacking merely the top surface of the sola...

Peveril Solar House

Welcome to Charging the Earth!

PEVERIL SOLAR is the first house in the UK to be entirely solar heated all year round! It is Carbon Net-Zero. It is an 'Active House' balancing inputs and outputs. PV generation and heating system consumption are in favourable balance using concepts of energy storage. Others claiming houses to be the first date from 2013 (and are unbuilt); this house exists and was carbon zero since 2011.

The name 'Charging' refers to 'storing energy underground': we have custom-built solar collectors, Surya Sunboxes, with ETFE front surfaces, to pump solar heat deep down into the earth. The building's heat pump gets all of this back in Realtime (immediately), Diurnially (later during the evenings) or Interseasonally (in Winter, months after the Summer).

Thus, we are augmenting the heatpump by storing long term heat in the summer, and we are defrosting the ground in winter-spring conditions, supplying solar energy directly to the heat pump, through its ground loop.

The five-way pentangle of Grid, Borehole, Heat pump, PV roof and Sunboxes have made the house Carbon Zero (for metered consumption). It's working, and we will continue to record data, to maintain that efficiency, and write it up in this website through to next year and beyond.

During theAutumn of 2012, we built a small house extension that is ultra insulated, with a higher energy gain than it loses.

Note, that we still have a net import of power from the Grid, because we still need power for lighting, cooking and appliances. But for the building emissions (as opposed to lifestyle emissions), we have achieved a credit balance of the regulated quantities, as recorded by meters.

The web-log follows the project from this general idea in Aug. 2009 to a technology of Surya Sunboxes, which seem to be effective - reducing energy costs of the house. Some of the Tabs will help you to get background and theory. You can click below to 'Follow Blog' to get email notifications - or email me. Please add Comments to the blog entries. If you find items in the Glossary that need explaining better, please ask. Thankyou!

Publications

Equipment sponsor

Kingspan, for Varisol Tubes

Equipment Sponsor

MG Renewables

Equipment sponsor

Ice Energy Heat Pumps

Equipment Sponsor

Holscot, for ETFE panels, re-fronting the Sunbox

About the Author...

David Nicholson-Cole is a Lecturer in Architecture at the University of Nottingham, with 35 years experience of architectural teaching and practice, which has included special interests in construction, building information modelling, tall building design and renewable energy technologies.

Finally, thanks to my deceased aunt, Margaret Cringle (1915-2008) whose legacy paid for most of the cost of this project - as one who was always turning lights out to save electricity, she would be very pleased!